An Atom-Economic Domino Reaction Process

Significance

The enantioselective, secondary amine catalyzed aminosulfenylation of α,β-unsaturated aldehydes is reported. Presumably the reaction proceeds via iminium ion 1, which is attacked by counterion 2 to generate enamine 3 highly enantioselectively. Subsequently, electrophile 4, containing a nucleo­fuge, is attacked by intermediate 3, liberating another nucleophile 2 and iminium ion 5. After hydrolysis product and catalyst are released. Intriguingly, the reaction equally occurrs without precedent addition of nucleophile 2, only in slightly longer reaction times.